Oil seal



NOV. 19,v 1935. R 1 GlTs 2,021,414

OIL SAL Filed Sept. ll, 1953 fnyen'ar UNITED STATES PATENT CFFICE on.snm.

` lumi J. Giu, chicago, nl. .application september 11, 193s, serialNaesassz (cl. 28s-1) I 10h-lm.

'rms invention relates to ou seals 'for rotating or reciprocating ularlyto seals of the positioned within a which the shaft or rod shafts androds and particcage type, adapted to be tubular housing through extends.

'I'he main objects of my invention are to provide an improved seal inwhich an annular axially extending packing is securely clamped to theside wall of thehousing in a manner that prevents inward squeezing ofthe body portion of the packing and permits substantially the endportion only thereof to contact the shaft; to provide an improved meansfor securing an annular packing to its enclosing shell; to provide animproved seal for reciprocating rods and shafts in which an inwardlyconverging axially extending annular packing is secured Aso as topositively prevent the same from becoming inverted by the motion of therod or shaft; and to provide an improved cage type seal structure thatis cheaper to manufacture.

A specific embodiment of shown in the accompanying Fig. 1 is a crosssectional this invention is drawing in which: view of an oil sealembodying my invention.

Fig. 2 is a sectional View line 2--2 0f Fig. 1. l

of the same taken on Fig. 3 is a sectional view of a modified form of myimproved seal.

Fig. 4 is a sectional tion of the seal shown In the form shown provedseal comprises arranged to surround view showing an applicain Fig. 3.

in the drawing the ima hollow shell or housing a rotating orreciprocating rod or. shaft and provided with an annular packing member,tele scopically inserted, which has an axially extending portionarranged to embrace the shaft with arranged to extend along andiiange-like portion contact the inner side ing. 'Ihe packing its endAmargin and a wall of the shell or housmember is secured by means of ametal ring positioned in the flange portion thereof and expanded againstthe side wall a spring actuated cont at the to urge the marginal mentwith the shaft.

of the shell or housing;

radially to clamp the same and acting member is provided shaft embracingportion of the packing edge thereof into engagedriven into or housing.In another contracting member structure and is emplo otherwise heldwithin a shaft form the spring actuated is omitted from the unit yed asa separate element.

-member and the It has long been the practice to provide selfcontainedoil seals for insertion as an assembled unit within a cylindricalhousing and theseseals are usually made up in a form similar to thatshown in the accompanying drawing. In these seals, however, the packingmember is formed with an annular radial flange at one end which ispositioned against the inwardly .flanged bottom of a cup-shaped shell orhousing `and is secured by means of an held under an axiallydirectedpressure against the packing member flange so as to clamp thesame against the bottom of the shell.

This arrangement is unsatisfactory because the pressure against theradial flange of the 15 packing tends to force the packing inwardlytoward the shaft when the packing becomes soft from usage and beingsoaked with oil, and as a result there is an objectionable long contactbetween th'e packing and the shaft along which oil 20 can creep or beworked. Also when there is an extended contact between the packing andthe shaft' there is much greater wear on both the shaft and the packingand the effective life of the seal is diminished.

vIt is because of this latter objection that certain seals such as thoseshown in my Patent No. 1,925,729 are arranged so that there is only aline contact between the edge of the packing shaft. However, it is foundthat even such an improvement is often defeated because of the manner inwhich the packing is secured to the shell or housing and it was in viewof this problem as well as others that the herein disclosed improvedsealwas devised.

In the form shown in Fig. 1 of the drawing the improved seal comprises ahollow annular shell or housing I, having a counterbore in each end suchthat an annular shoulder or flange 2 is formed on the inner sideintermediate the ends. An annular packing member 3, formed to provide anannular shoulder 4 having an axially extending ange or collar 5 thereon,is positioned in oneof the counterbores of the shell l so that theshoulder l of the packing abuts the shoulder 2 of the shell, the ange 5being formed with an outside diameter such that it will substantiallyfit the sides of the counterbore in which it lies.

The body of the packing 3 is arranged to be mainly spaced away from ashaft 6 passing there- 50 through, which it is intended to seal againstthe passage of oil, and is preferably tapered inwardly so that only theouter marginal edge 1 is in contact with the shaft. This providessubstantially a line contact between the packing and the annularclampingring which is 10 f shaft the pressure and effectiveness of whichcan be more readily controlled.

A metallic clamping ring l, preferably endless, is positioned in thepacking member adjacent the flanged portion thereof and is mechanicallyexpanded or forced radially after insertion so as to clamp the flangeagainst .the side wall of the shell or housing I and permanently securethe packing to the shell. 'lhe packing 3 is preferably formed so thatthe flange 5 is positioned atV the outer edge or margin of the shoulder4 thus providing a ilat bottomed counterbore in the packing member inwhich the clamping ring l is seated before it is expanded. With such anarrangement the clamping ring, when expanded, clamps the packing membertightly against the shoulder 2 of the shell or housing as well asagainst the side wall thereof and obviates the possibility of thepacking buckling adiacent the shoulder I and becoming inverted due toany reciprocating action of the shaft. It is this feature of theimproved seal that makes practical its application to reciprocable rodssuch as the piston rods of shock absorbers and the like where oil isemployed under pressure.

The end of the shell I adjacent the flanged portion of the packing isprovided with a second counterbore formed to receive a ilat washer lwhich serves to -reduce the aperture at that end of the seal and alsoprevent the possibility of` axial shifting of the ring I and thepacking. 'I'he marginal edge of the seal is spun or rolled over theouter margin of the washer 9 after assembly to secure the same in place.

The counterbore at the opposite end of the seal shown in Fig. 1 isformed to receive and house the packing contracting means whichcomprises an axially shiftable ring Il having a frustoconical bearingportion II arranged to bear against the tapered rim 1. of the packingmember.

The ring Il is urged axially, to contract the rim 'I of the packingabout the shaft, by means of a plurality of springs I 2 which arecarried by a fiat ring I3 seated in a counterbore at the end margin oithe shell and Secured by spinning or rolling the said margin inwardlyover the ring.

In order to securely grip the flange I of the paclnng member a pluralityof grooves I4 are preferably formed on the outer surface of the ring 8and on the inner surface of the shell or housing I adjacent the flange5. 'I'hese grooves may be of the same form as screw threads, but arepreferably cut circularly rather than helically. With such anarrangement the ridges between the grooves of the ring l are forced intothe iiange 5 of the packing. as the ring is radially forced or expanded,and the ilange is' forced into the grooves of the shell, thus providinga definite bite between the packing and its securing means.

In the modified form of the improved seal shown in Fig. 3 the shell orhousing I is provided with an inwardly projecting annular flange orshoulder I5 at one end and is provided with a counterbore at itsopposite end to form a Second shoulder I6 intermediate the ends. Thepacking member 3 of this seal is of the same form as the one used in theseal shown in Fig. 1 and is positioned in the shell with its shoulder Iabutting the end shoulder I5 of the shell. In this case the shaftembracing portion 'I of the packing extends axially beyond the end ofthe shellV I.

The packing member is secured to the shell by means of a groovedradially expanded ring in the 'same manner as has been described aboveand a l.the cup-shaped member I9 the like l preferably made iiat washerI'I is seated in the counterbore against the shoulder I6 to prevent anypossibility of axial movement of the packing and securing ring.

A flexible washer I l arranged to embrace the 5 shaft C, passing throughthe seal, is seated in the counterbore against the washer I1 and acup-shaped ring or member I9-having an axially extending flange 2l ispositioned over the iiexible washer I8 to hold it in place. 'I'he ange2U of 10 is arranged to extend inwardly to contact and secure the washerI I and the member I S is held in place by the spun or rolled overmargin 2| of the shell. Y

This form of seal is particularly adaptable for Sealing the piston rodof a shock absorber or and a typical application of the same is orbearing housing 22 on the device to be sealed and is positioned on theouter side of the bearing 23. The packing contracting ring Il isdisposed over the axially projecting portion of the packing between theseal I and the bearing and is actuated by a helical spring 2l disposedbetw the ring I 0 and the 25 bearing 23. the spring 2l being compressedbetween the bearing and the contracting ring.-

In the manufacture of the improved seals shown in the drawing the shellor Vhousing I may be made in any suitable manner and of-any suitablematerial... owever, in order to reduce the cost of manufacture itispreferable that they be made as die castings. The securing ring I isof a somewhat ductile metal such as brass and the contracting ring Iland washers l, Il, I I and Il may be metal stampings. The packing memberl is preferably of a flexible material such as leather and the flexiblewasher Il may be of felt or other suitable material.

In operation and use the improved seals, which are preferably made up inunits of predetermined diameters, are driven, or set and clamped, in ashaft or rod housing. 'I'he shaft or rod is then passed through the sealand the device is ready for operation. 4

The proportions-of the seal are such that the tapered portion 1 of thepacking will lightly contact the shaft when the same has been passedthrough the seal and the contracting member, which is always under thesprings urging it against the packing, maintains a continuous linecontact between the shaft and the packing because of vits frustoconicalwasher engaging portion, thus, automatically compensating for wear oneither the 5 5 shaft or the packing.

In the embodiments of this invention shown in the drawing the packingmember is shown surrounding the shaft and supported by the"` structurein which the shaft is housed. How- 00 ever, the packing might bedirectly supported on and carried by the shaft in a reversal of the*structure shown. and itis intended that the claim cover such anarrangement.

Although but two specific embodiments of this 05 invention are hereinshown and described it will be understood that details of the structuresshown may be altered or omitted without departing from the spirit ofthis invention as denedby the following claim.

I claim:

An oil seal comprising a hollow annular shell Surrounding a shaft andhaving an internal radial flange disposed intermediate its ends, ailexible annular packing member having an axially 75 shOWn a constantpressure from extending portion projecting over and beyond the inneredge oi said ilange and converging inwardly toward said shaft. the outersurface of the converging portion of said packing being tapered inwardlytoward said shaft, a radial shoulder on said packing member abuttingsaid flange, an axially extending collar on said shoulder arranged toengage the wall oi' said shell, an annular clamping ring disposed withinsaid collar and expanded radially to clamp said collar to said shell,said clamping ring and the adjacent wall of said shell having annulargrooves into which the surfaces of said collar are forced as the same isclamped between them, an axially shiftable ring housed within said shelland having a frusta-conical inner margin arranged to engage the taperedportion of said packing member, a ilat ring secured to the end of saidshell for retaining said shiitable ring, and means disposed between saidflat ring and said shiftable ring arranged to urge said shiftable ringaxially to contract the tapered end margin of said packing member aboutsaid shaft.

REMI J.- GITS.

